Super Bowl lineup: Ray Lewis, Colin Kaepernick and the Harbowl

Back in November, Jim Harbaugh told us that he planned to ride the "hot hand" at quarterback. Two months later, Colin Kaepernick's blistering right paw has slung the 49ers into the Super Bowl. In doing so he has vindicated his coach's greatest gamble.

In truth, the debates over Harbaugh's decision to promote Kaepernick above Alex Smith died down a little while ago. There may never be a quarterback less deserving of losing his job than Smith – who had done everything the coaching staff asked and was enjoying the best season of his career up until his week 10 concussion against St Louis. But when your replacement is playing as well as Kaepernick did in obliterating the Green Bay Packers in the divisional round, nobody is going to sit around mourning your absence.

Before this Sunday, though, it was still too soon to declare Harbaugh's switch a total triumph. Because as he deliberated and dwelled over his options at quarterback in November, the foremost question in the coach's mind will not have regarded which player was more talented or could put up the gaudiest numbers. The only thing that truly concerned Harbaugh was which player gave his team the better chance of playing in this year's Super Bowl.

Of course, Kaepernick possessed greater upside – three years younger and with more impressive physical tools – and on another team there might have been an argument for long-term thinking. But after last year's NFC title game defeat to the Giants, Harbaugh knew he had the rest of the pieces in place to make a run at a championship. In the NFL, those windows close quickly.

As unthinkable as it seems today, there was a strong case to be made for sticking with Smith. He had taken his team to the brink of an NFC title just one year previously – and although he came up short against New York last January, he seemed to have learned a few lessons since then. He was a safe pair of hands who could get the job done for a San Francisco team that was good enough not to need a superstar under center.

Except that on Sunday, they did need that superstar. The Falcons had burst out of the gates to a 17-0 lead, Matt Ryan and Julio Jones looking so perfectly in sync that you wondered how they would ever be contained. It takes strong nerves to come back from that sort of deficit in an environment as hostile as the Georgia Dome. It also takes a quarterback capable of winning games, not just managing them. Recovering from a 17-point deficit to win represented the third-largest comeback in NFL postseason history.

That is not to suggest Kaepernick carried his team alone, or carved up Atlanta single-handed. San Francisco battled back into the game with a combination of an effective ground game, smart defensive adjustments and improved blocking of both the run and pass.

But they also leaned on a quarterback who showed himself adept at exploiting the defense's weaknesses, whether that was through regular targeting of Vernon Davis – a player he had barely thrown to over the previous seven games – or knowing when to hand the ball off to Frank Gore in the read-option offense. His numbers – 16 of 23 for 233 yards and a score, plus two carries for 21 yards – are solid enough, but they do not speak to the poise, the decision-making and the calm he brought to his offense.

Perhaps the 49ers would have made the Super Bowl with Alex Smith at quarterback, too, and perhaps he was deserving of the chance to lead them there. But nobody will be dwelling on such hypotheticals in San Francisco this morning, because Colin Kaepernick did get them there. And that, when assessing Harbaugh's biggest call, is all that really matters.

The other Harbaugh might know what he's doing too

Brace yourselves for the HarBowl – as San Francisco head coach Jim Harbaugh takes on his older brother, the Baltimore Ravens coach John, at Super Bowl XLVII. Last season they became the first siblings ever to coach against one another in the NFL – during a Thanksgiving Day game in Baltimore, which the Ravens won 16-6. Now they will be the first to do so with the title on the line.

This match-up was so nearly a reality last year, when both brothers lost their respective conference title games by just three points. Asked last week if they had ever discussed the prospect of meeting in the Super Bowl, John replied:

"Not that I'd ever admit to."

The possibility must at least have been on the minds of two men who talk by phone every week. With each sending game film to their father Jack Harbaugh – formerly a successful college coach – on a regular basis, you have to wonder whether either has woken up this morning regretful over one too many trade secrets leaked at a family dinner somewhere down the line.

Jim has always carried the higher profile – the result, at least in part, of his more successful playing career. Exactly 15 months younger than his brother, Jim enjoyed 15 years as an NFL quarterback – split between six different teams. After retiring in 2001, he needed just three years to land his first head coaching job with the University of San Diego.

John, a former defensive back, never played beyond college and instead spent two decades climbing the coaching ladder before finally getting his first head coaching gig in Baltimore in 2008. At the time it was considered a surprise appointment, but a 62-30 record (including playoffs) since then has more than vindicated the Ravens' decision. Only one head coach has won more games over the same period – Bill Belichick, whose Patriots John defeated on Sunday.

And if Jim's gamble on Kaepernick was rewarded this weekend, then John can claim similar success with his boldest move. The Ravens head coach's decision to fire offensive co-ordinator Cam Cameron in mid-December raised more than a few eyebrows – read by many as a panic move from a team who had dropped back-to-back games and were threatening to lose their grip on the AFC North.

Instead, Jim Caldwell's elevation from quarterbacks coach to Cameron's replacement has worked out beautifully. Baltimore would lose the next game to Denver, 34-17, but since then they have averaged 28 points and 431 yards per game. Caldwell has encouraged quarterback Joe Flacco to both spend more time outside of the pocket and take regular shots downfield. The results have been breathtaking.

In three playoff games, Flacco has thrown for 853 yards, eight touchdowns and no interceptions. Amid blustery, frost-bitten conditions at Gillette Stadium in the AFC title game, Flacco thoroughly outperformed New England's Tom Brady – just as he had Peyton Manning in Denver two weeks previously.

That is a testament to the quarterback himself, as well as a remodeled offensive line which has done a great job in protection. But it is also to the credit of his coaching staff.

His team-mate Terrell Suggs stole some headlines, too, commanding reporters to "tell 'em [the Patriots] to have fun at the Pro Bowl" as he made his way back to the locker room after the game. "These are the most arrogant pricks in the world starting with Belichick on down," he is reported to have added. "That's funny, ever since SpyGate they haven't been able to win." He later tempered those comments, saying: "All BS aside they are a hell of a ball club ... They have the right to be arrogant."

The single most critical defensive play of the game for Baltimore was not by Lewis or Suggs, though, but instead the safety Bernard Pollard. It is a name which recalls grim memories for New England fans. A man jokingly referred to as "Patriot killer" by his team-mates has been involved in four significant New England injuries since 2008.

Tom Brady, in that year, was the first – blowing out his knee on a tackle from Pollard, then a Kansas City Chief. One season later the same player, now with the Houston Texans, was closing in on Wes Welker when the receiver tore his ACL while attempting to cut away. Then, in last year's AFC title game, Pollard's tackle on Rob Gronkowski left the tight end with a high ankle sprain which would severely limit him in the Patriots' subsequent Super Bowl defeat.

The fourth incident arrived on Sunday, when Pollard knocked Stevan Ridley briefly unconscious on a helmet-to-helmet collision in the fourth quarter. The running back fumbled and Baltimore, leading 21-13 at the time, recovered at the New England 47. Their ensuing possession ended with a touchdown which extended the Ravens' lead to 15 points with just 10 minutes remaining – an advantage they would never relinquish.

There was nothing illegal about Pollard's hit – Ridley was running the ball and had himself lowered his head into the contact – but it is equally not the sort of play that the league wants to see celebrated at a time when the long-term damage caused by head injuries is at the top of the player safety agenda.

Afterwards, Pollard said:

"It's just a tackle. It's football. He broke a hole and we filled. That's fine. That's football. I hope he's okay. We're competitive in the moment. But when everything calms down you want that guy to be okay."

Last week Pollard had struck a similar note, telling NFL.com he did not derive any joy from his reputation of doing damage to the Patriots' players:

"Anything that I've done, I don't celebrate with that. I don't laugh when people come up to me and call me 'The Brady Killer'. I don't laugh at that. I'm looking at a man that I respect. I respect Tom Brady with everything that I have. I know his story, I respect him, first of all, because he's a man. I respect him because he's a player. Honestly, I don't get excited because of that. When it's all said and done, that man had to do the treatment, he had to do everything else to come back. Nothing is done maliciously."

Ridley, encouragingly, walked off the field under his own power yesterday, though the long-term damage of a single hit like that may never be ascertained. What we do know is that once again a Bernard Pollard hit dealt New England devastating short-term damage.

We have likely seen the last of Tony Gonzalez

One of the most heart-breaking images of Sunday night was that of the Falcons tight end Tony Gonzalez – perhaps the greatest ever to play his position – slumped forwards on a small chair in front of his locker at the Georgia Dome. Once again Gonzalez had more than done his part, catching eight passes for 78 yards and a fine touchdown – for which he had timed his cut perfectly to move away from his defender before making a falling grab in the front of the end zone.

Gonzalez did not give firm confirmation of his retirement, but he did make it pretty clear that he is still leaning in that direction:

"It's probably the last time I'm going to wear that uniform. I didn't want to take it off, to tell you the truth. All good things come to an end and, like I said all season long, this is probably my last one. What an unbelievable ride."

He insisted that he would have "no regrets - not one" if he did choose this moment to walk away, adding:

"I don't want anyone to feel sorry for me."

The rest of us are instead left feeling sorry for ourselves at the thought of never again getting to watch a player who re-defined his position – blazing a trail for pass-catching tight ends. His 1,242 career receptions are second only to Jerry Rice. He leads the next-best tight end, Shannon Sharpe, by more than 400 catches. In this, his 16th season in the league, he reeled in 107 balls for 1,059 yards and 10 touchdowns (including the postseason).

Nobody doubts that Gonzalez could come back and play to a high level again next year, and the Falcons undoubtedly wish he would. But after finally recording the first playoff win of his career last week, the only thing that could bring Gonzalez back would be the desire to win a Super Bowl. Atlanta are well positioned to be a contender again, but even for a good team, it is a long, arduous road to get to that point.

It is his prerogative to decide that he has had enough, that the time has come to move on – to give his body a break and walk away. Even if the rest of us quietly wish that he wouldn't.

• One enormous question for San Francisco to address over the next fortnight: how do you solve a problem like David Akers? The kicker had already missed more field goals this season than anybody else in the league, and on another day his failure to convert from 38 yards midway through the third quarter could have been the difference between winning and losing. Going into a Super Bowl with a kicker you cannot trust is not the sort of spot that anybody wants to be in – least of all a team who blew the NFC title game last year with the help of some critical special teams gaffes.

• All eight of the NFL's head coaching vacancies have now been filled, but there is consternation around the league that none went to an African-American. The Rooney Rule obliges all teams to interview at least one minority candidate, but of course all are free to hire as they see fit. The issue is an incredibly delicate one, with teams well within their rights to decide themselves which coach best suits their team's needs – but the league battling with a huge perception problem. Following the sackings of Romeo Crennel and Lovie Smith, there will be just three African-American head coaches in the NFL next year.

Over the next two weeks we will have all the build up to the Super Bowl and extensive live coverage of the game itself. Plus we will look at the end of the season for all the other NFL teams.